Environmental Statement volume 4 - Chiltern Evergreen3

Chiltern Line September 2009Reptile Report2.0 MethodologyData Search2.1 The National Biodiversity Network (NBN) web-resource was searc hed for recor ds of reptileson and within a 500 metre radius of each site, as this was the initial buffer given for the GreatCrested Newt work.Field Survey2.2 Reptiles need to warm in the sun, but prefer to do so in cove r. Therefore the use of artificialrefugia encourages reptiles to be foun d in specific areas rather than the le ss fruitful transectsurvey.2.3 The survey method requested by ERM used artificial refugia made from squares of roofing felt0.5m 2 with a den sity of a pproximately 20 refugia at ea ch site, but with 5 0 at the largerBicester site. The refu gia were evenly placed throughout the h abitats and were left to beddown for 1 week. Du ring this time, they develop favourable conditions (e.g. suitable humidityand tem perature gradient) and the re ptiles be come more fa miliar with them . To asse sspresence o r absen ce, the refugia we re chec ked on ce ea ch day for 7 days durin g optim alweather conditions (i.e. between 11 and 19C with intermittent sunshine and little or no rain),in accordance wi th recommendations set out by Hill et al. (2005 ), but were rested atweekends to gain better results. The refugia were collected upon completion of the fieldwork.2.4 Reptile surve y equip ment wa s set out on the 15 th of Septe mber 2009. T he e quipmentconsists of artificial refugia made of 4 millimetre torch on roofing felt that is cut into 50 x 50centimetre mats. The felt warms up quickly and retains the heat well, attracting reptiles.2.5 The refugia were set out at variou s po ints al ong th e rail way i dentified by ERM du ring thei rinitial walkover of the site, but if thi s was not possible due to health and safety on a live railline then the mats we re placed as close to the original site as possible in suitable habitat andwhere access permitted. 8 sites were surveyed:Bicester Town Station (SP 585 21 8, 0.5 hectares, 20 refugia) substituted for O xfordStation (SP 503 071). Wolvercote Tunnel Sout h (SP 497 1 00, 0. 7 hect ares, 20 ref ugia) substituted forUpper Wolvercote (SP 498 092).Wolvercote Tunnel North (SP 497 103, 1.2 hectares, 20 refugia).Water Eaton South (2.04 hectares, 20 refugia) substituted for Water Eaton North (SP513 132).Oddington (SP 593 157, 1.58 hectares, 20 refugia).Wendlebury (SP 563 185 3.04 hectares, 19 refugia).Langford Lane (SP 575 203 0.02 hectares, 20 refugia).Langford Ind ustrial E state, split into So uth (SP 59 5 223, 15.8 hectares, 3 0 ref ugia)and North (SP 595 226, 1.66 hectares, 20 refugia).Keystone Environmental 3